Whisk eggs and sugar in a bowl until light and fluffy.

Gradually add kefir while continuing to whisk.

In a separate bowl, combine flour, salt, baking soda, and ammonium bicarbonate.

Add dry ingredients to wet ingredients and mix until just combined; lumps are okay.

Let the batter rest for 30 minutes.

Heat a non-stick griddle or frying pan on medium-low heat.

Pour 1/3 cup of batter onto the hot griddle to form a 4-5 inch circle.

Cook until the top is bubbly, then flip and cook the other side until golden brown.

Serve warm or cold with desired toppings, such as butter, sugar, sour cream, jam, or brunost.

Fold the pancake in half before serving.